1. Field of the Invention
This invention relates to a helical formed take-up liner for uncured rubber members and a method of producing the same.
2. Related Art Statement
The uncured rubber members used, for example, for the manufacture of tires are frequently stored for a time between a step of supplying these members and a step of using these members to manufacture a tire. In this case, an elongated band-like uncured rubber member is usually stored as a scroll. In general, uncured rubber member is temporarily stored in form of a scroll by sandwiching between a pair of take-up liners in order to prevent the deformation of this member.
When the uncured rubber member to be stored is a contoured rubber member used, for example, in top and side treads, inner liner or the like, as shown in FIG. 3, the thickness of the uncured rubber member 7 differs in the widthwise direction thereof, so that when the uncured rubber members 7 are taken up together with take-up liners 1 at such a state that the convex portion of the member 7 locally protrudes from the liner 1, the outer diameter becomes different in the widthwise direction, and consequently the uncured rubber member 7 dewound in use takes a curved form in the longitudinal direction thereof as shown in FIG. 4. Furthermore, when the uncured rubber member is taken up as a continuous scroll, a portion of the uncured rubber member located at the inside of the scroll is crushed and deformed by its dead-weight. Moreover, wrinkles are produced in the liner, which are transferred onto the surface of the uncured rubber member to reject the rubber member as inferior goods. Therefore, it is attempted to improve the take-up liner.
In the conventional used take-up liner, a texture of a holding-up cloth reinforcing the liner is transferred onto the surface of the uncured rubber member during the taking up to lower the tackiness of the rubber member, and also the change of tackiness is caused in accordance with the taken up positions (outer, middle and inner positions). Therefore, when the laminating operation using such rubber members is carried out at the use step, there are caused the following problems:
(i) the bonding force to the other rubber member is weak; PA0 (ii) the operability and efficiency considerably lower; PA0 (iii) air is undesirably entrapped in the product; PA0 (iv) the adhesion force at the interface between the rubber members as a product is poor; and PA0 (v) volatile matter for rubber, rubber cement or the like is used for improving the bonding force, which takes extra cost and is unfavorable in view of operation environment.
In order to solve these problems, there is proposed a take-up liner as shown in FIG. 5, wherein a flexible foamed body 3 having a thickness of about 3-5 mm is adhered to each surface of a long and inextensible band-like reinforcing cloth 2, and an extensible holding-up cloth 4 is adhered to an outer surface of each of the foamed bodies 3, and a sheet-like elastomer 5 such as urethane, polyester, nylon, polypropylene, styrene-butadiene rubber (SBR), chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR), nitrile, silicone rubber or the like is further bonded thereon. In this liner, the movement of the extensible holding-up cloth 4 is restrained by the sheet-like elastomer 5 to form wrinkles 8 at the inside of the liner as shown in FIG. 6, which are also undesirably affected to the uncured rubber member during the taking up as previously mentioned.